This invention relates generally to the treatment of water which passes into the piping of a drainage system by way of a storm drain and relates, more particularly, to filtration systems through which drainwater is routed for purposes of filtering contaminants from the drainwater.
It is known that residue from oil and gasoline spills at service stations, parking lots or similar sites commonly remains at the site of the spill until it is washed away with water by way of a rainfall or a hose-cleaning operation. Of, course, as the residue and/or spilled material is washed to a drain, it is likely to be carried to and mixed with the water supply (e.g. lakes, etc.) from which drinkable water is taken. Similar problems and environmental concerns arise at alternative sites, such as in a leaching pool designed as a detention basin, for filtering, for example, wastewater, stormwater, free-phased organics, petroleum spills, nonpoint source discharge water, vehicle washdown wastewater, wastewater from secondary containment dikes, excavation and construction sites, underground storage tank removals, emergency response conditions, remote wash down areas, and captured water at stream crossings for timber cutting sites.
It is an object of the present invention to provide a new and improved means for filtering water which flows into a storm drain.
Another object of the present invention is to provide a new and improved drainwater treatment system which is positionable within a horizontal flow passage of a storm drain system and which provides an improvement upon the structure and filtration capabilities of the drainwater treatment systems of the prior art.
Still another object of the present invention is to provide such a treatment system which provides a relatively high exposure of drainwater to filter medium as drainwater flows through the treatment system.
Yet another object of the present invention is to provide such a system which is uncomplicated in construction and effective in operation.